Liquid pump



Patented Dec. 18, 1934 UNITED STATES PATENT OFFICE "1,984,391 LIQUIDPUMP Robert s. Basseit, Buffalo, N. Y. Application December 9,1931,Serial No. 519,967

3 Claims. (01. 221-95) My invention relates to improvements in liquidpumps which will draw inboth liquids and gases through the intake butfrom which the discharge oi. liquids only is desired from the outlet.MY- 5 invention relates particularly to grease pumps for handlingautomobile transmission and differential grease, which is pumped fromsmall containers which are frequently emptied, with the result that airenters the intake of the pump, the grease in the container havingreached a low level near the pump intake.

The object of my invention is to provide a means to separate gases, suchas air, from liquids, such. as grease, and to discharge liquids onlythrough the main outlet opening, the gases; together with a small amountor grease, being discharged through a secondary opening. 4

The result of my invention is to provide a practical method for therapid dispensing of grease directly from a hose without the necessity offilling measuring containers with the grease to assure that air was notbeing measured together with thegrease by the measuring unit, which, in-

my drawing, is shown as a liquid operated grease meter the usual type.

, A novel feature of myinventlon is the discharge of the gases hack intothe grease containersothatthesmallquantitiesotgrease,

which pass out with the gases, are automatically.

the same inside-diameter thromhout its-length.

'lheexactcross-sectionoithegasdischarge-mhe,hothattheupperneckandatthelowerportlon.isnotimportanthut,preterahly,slmuldbein thealnpeotasquareoracircle.Thetubeas soshcwnisreadilybendahletoalloweasylining upottheassembly.

In thisapplication'the'greatest width of theopeningatanysectiontakenacrcssthetubewill be spoken of as the "width"though. inthe 56 o! a circular cross-section, which is the cus- .tomaryform, the width, of course, will be the diameter.

In my drawing the figure is a central longitudinal view of my improvedliquid pump, showing a section through the pump cylinder and the gasdischarge tube, and showing the outside of the liquid operatedmetering'devic'e and discharge P pi 4 Pump cylinder 1 is withingreasecontainer 2 and passes through grease container cover 3 in theusual manner. Driving pinion 4 and rack 5 move piston rod 6 up and downwithin pump cylinder 1. The exact construction of the pump or liquidcirculating device is not restricted to ihe construction shown but maybe of any suitable construction for creating a flow of grease toward themeasuring device.

. '1 is the upper portion 01' the pump enclosing rack 5. 8 is thebeginning of the discharge passage from the liquid circulating device.91s a liquid operated meter of the usual type. 10 is the dischargetubing or pipe leading fromth'e lquid meter 9 and may be fitted with aconventional shut-oi! valve 11. which prevents the hose from drainingwhen the pumping operation is stopped.

Elements 1 to 11 inclusive are all shown 01' conventionaldesign'and arenot limited to the 13 in one' direction in' the usual manner. 19 is themain delivery opening iron the pump on which is mounted the liquidoperated meter 9.

In the construction shown the pump discharges through an outlet fitting15, which screws into the upper portion otthe pumpcasing 7. Outletfitting 15 could have been shown integral with casing'l,astheexactconstruction onthis point is not important, but theconstruction shown of having'fitting 15 as a separate piece wouldprobably be moteconvenient tor most-installations.

Gas discharge tube iohas one end emptyingintogreasecontaine'r2andtheotherendprojectingintothedmmleadlnlfromtheend-oigas'disclnrgetube 16. in orificel'lissmallerinareathantheopeningin tube loatapointbelowtheoriflce.lsisabindingnuttoholdtubelsfirmlyinplaceinthe usual manner tor-theconstniction shown.

when the pumpis operated liquidis pumped out of container 2 up-andoutthrough discharge 'pumptothemeter. 17isanorific'eattheinlet passage8. When the level of the liquid in. container 2 is so low that air orother gases can pass in through foot valve 12, a mixture of liquid andgases is pumped. Meter 9 requires some pressure to operate it so thatthe pressure in discharge opening 19 isslightly greater than thepressure in discharge tube 10 leading from the meter. There is, ofcourse, practically no pressure above atmospheric pressure withincontainer 2, as container 2-and container cover-3 do not enclose thesupply of liquid so tightly as to exclude theadmittance of air fromoutside the container. The pressure at the lower end of gas dischargetube 16 is, therefore, practically atmospheric only and, therefore,somewhat lower than the pressure at delivery opening 19. This causes aflow of liquid downward through tube 16 at all times. As the inside oftube 16 is considerably larger than the opening in orifice 1'1, theliquid, which enters through the orifice does not completely fill tube16, but runs down one side of it. Tube 16 below the orifice is,therefore, filled partly with liquid and partly with air. Because of theair within the tube, the pressure within the tube just below orifice 17is practically the same as the pressure at the lower end of tube 16. Itorifice 17 were omitted, the tube would be filled practically solid withliquid when grease is measured, with the result that the pressure at theupper end of tube 16 would be much higher than in the constructionprovided for by my invention.

When a small quantity of air passes up through the pump and reachesorifice 1'! it can readily pass down through the orifice rather thaninto meter 9 because of this difference in pressure.

In my experiments I have found that there are certain limits to thelength of the opening of orifice 17 in proportion to the width of theopening, this proportion being covered in the claims. It can readily beseen that ii the restricted neck at the upper end of the tube or theorifice, is too long that the advantage in the diflerence of pressure,which controls the flow of the air, will be overcome by the friction ofthe grease which enters the orifice together with the air, this greaseforming a seal if the neck is too long.

The exact proportions of the opening in orifice 17, as compared with thearea of tube 16, are controlled by the viscosity of the liquid to behandled. With a very thin liquid the necked opening or orifice at theupper end or the tube can approach in size the tube itself. Forextremely viscous liquids a large tube must be used together with asmaller orifice to allow the proper movement of the contents of thetube.

Having thus described my invention what I claim as new and desire tosecure by Letters Patent is:

1. A dispensing and measuring apparatus for viscous substances, such asgrease, comprising 8 meter, 2. container for the grease, a pump havinits inlet below the level of grease in said container and its outletconnected to the meter, a dischar e line and a discharge nozzle, saidpump, meter, discharge line and nozzle being mounted upon said containerand connected together so that upon actuation of said pump grease willfiow from said container through said meter, discharge line and nozzlein succession, and a bypass having its outlet in said container abovethe levelof grease therein so as to be remote from the inlet to saidpump and so that the grease within the container does not obstruct saidoutlet and having its inlet in the path of the grease between said pumpand meter so that air entrained in the stream of grease will be returnedto said container above the grease therein, said bypass having arestricted neck section near the bypass inlet, substantially as and forthe purpose described.

2. A dispensing and measuring apparatus for viscous substances, such asgrease, comprising a meter, a container for the grease, a pump havingits inlet below the level of grease in said container and its outletconnected to the meter, a discharge line and a discharge nozzle, saidpump, meter, discharge line and nozzle being mounted upon said containerand connected together so that upon actuation of said pump grease willflow from said container through said meter, discharge line and nozzlein succession, and a bypass having its outlet in said container abovethe level of grease therein so as to be remote from the inlet to saidpump and so that the grease within the container does not obstruct saidoutlet and having its inlet in the path of the grease between said pumpand meter so that air entrained in the stream of grease will be returnedto said container above the grease therein, said bypass having arestricted neck section near its upper end, substantially as and for thepurpose described.

3. A dispensing and measuring apparatus for viscous substances, such asgrease, comprising a meter, a container for the grease, a pump havingits inlet below the level of grease in said container and its outletconnected to the meter, a discharge line and a discharge nozzle, saidpump, meter, discharge line and nozzle being mounted upon said containerand connected together so that upon actuation of said pump grease willflow from said container through said meter, discharge line and nozzlein succession, and a bypass having its outlet in said container andhaving its inlet in the path of the grease between said pump and meterso that air entrained in the stream of grease will be returned to saidcontainer above the grease therein, said bypass having a restricted necksection near the bypass inlet, substantially as and for the purposedescribed.

ROBERT s. BAssETr.

